Stability of beta-galactosidase messenger ribonucleic acid in Escherichia coli.
Ben-Hamida, Fakher (Washington University School of Medicine, St. Louis, Mo.), and David Schlessinger. Stability of beta-galactosidase messenger ribonucleic acid in Escherichia coli. J. Bacteriol. 90:1611-1616. 1965.-Synthesis of beta-galactosidase stops within several minutes when preinduced, permeaseless cultures are diluted into medium containing 40 mug/ml of 5-fluorouracil (5-FU) but no inducer. However, if inducer (isopropylthiogalactoside) is left in the medium, enzyme formation in the presence of 5-FU continues for at least 11 min. Thus, inducer may increase the differential metabolic stability of the corresponding messenger ribonucleic acid (RNA; defined as the capacity to produce measurable enzyme) in inducible strains. However, such an interpretation requires that 5-FU rapidly arrest the further synthesis of messenger RNA competent to form active enzyme. C(14)-5-FU, like uracil, does appear to enter cells without measurable lag, saturating the pool of uracil nucleotides, and thereby the messenger RNA being formed, within several minutes. That 5-FU acts very quickly is also supported by the similar continuation of enzyme synthesis in the presence of inducer and antibiotics (actinomycin D and proflavine) which shut off all RNA synthesis, as well as by the response to 5-FU of enzyme synthesis in various constitutive mutants.
D000166:Acridines / Q000494:pharmacology; D003609:Dactinomycin / Q000494:pharmacology; D004926:Escherichia coli / Q000378:metabolism*; D005472:Fluorouracil / Q000378:metabolism; D005696:Galactosidases / Q000096:biosynthesis*; D066298:In Vitro Techniques; D008962:Models, Theoretical; D009154:Mutation; D012329:RNA, Bacterial / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000096:biosynthesis*
D000166:Acridines; D012329:RNA, Bacterial; D012333:RNA, Messenger; D003609:Dactinomycin; D005696:Galactosidases; D005472:Fluorouracil